Peer Reviewed


Moyamoya Disease

Kirill Alekseyev, MD, MBA • Andrew Malek • Matthew Milan • Bilal Chaudhry, MD

Post Acute Medical Rehabilitation Hospital of Dover, Delaware

Alekseyev K, Malek A, Milan M, Chaudhry B. Moyamoya disease. Consultant. Published online July 30, 2020. doi:10.25270/con.2020.07.00011

Received March 18, 2020. Accepted July 5, 2020.

The authors report no relevant financial relationships.

Kirill Alekseyev, MD, MBA, Medical Director, PAM Rehabilitation Hospital of Dover, 1240 McKee Rd, Dover, DE 19904 (


A 54-year-old African American woman with a medical history of type 2 diabetes, hyperlipidemia, iron-deficiency anemia, hypertension, stroke, and seizures presented to a rehabilitation hospital with a diagnosis of moyamoya disease (MMD).

The patient explained that her symptoms of constant right foot pain and “headaches worse than migraines” had begun approximately 7 years prior. She stated that the headaches and lower-extremity pain were associated with diaphoresis, appeared suddenly and simultaneously, and were nonradiating, with a grade of 9 on a 10-point pain scale. She recalled being rushed to a local hospital at that time, where she was admitted for 11 days with the diagnosis of ischemic stroke. She reported that she still was experiencing these symptoms, which were alleviated by pregabalin, 225 mg, and combination acetaminophen, butalbital, and caffeine.

Approximately 5 years ago (2 years after the onset of symptoms), the patient had experienced another ischemic stroke and had been placed on apixaban and aspirin. She then had a recurrent ischemic stroke approximately 3 years ago (4 years after the onset of symptoms) with baseline right lower-extremity weakness and expressive aphasia.

The patient was diagnosed with MMD approximately 2 years ago after having had a fall; at that time, computed tomography (CT) scans of the head showed multiple subacute/chronic bilateral frontoparietal infarcts, and cerebral angiography demonstrated occlusion of the bilateral internal carotid arteries. Perfusion-weighted magnetic resonance imaging with acetazolamide was also performed, the results of which demonstrated bilateral perfusion delays, worse in the left hemisphere compared with the right.

In light of these findings, the patient underwent bilateral craniotomy with left indirect extracranial-intracranial artery anastomosis (EC-IC bypass) and 3 weeks later underwent right direct EC-IC bypass. An immediately postoperative CT scan of the head (Figure) showed expected changes from interval right craniotomy and EC-IC bypass, including a small extra-axial collection and a small subarachnoid hemorrhage. In addition, imaging also showed a 2-mm right-to-left midline shift with no evidence of acute ischemia.

CT scan of the head
Figure. CT of the head demonstrating immediate postoperative changes. The 4 images show a 2-mm right-to-left midline shift with no evidence of acute ischemia, a small extra-axial collection, and expected changes from interval right craniotomy and EC-IC bypass.

The patient stated that after the procedure, she was placed on levetiracetam for seizures; aspirin; oxycodone for pain; atorvastatin, 80 mg; midodrine; folate; and ferrous sulfate, 325 mg.

The patient lives with her mother, and a certified nursing assistant comes to her house daily to assist her with everyday tasks, which include getting in and out of bed and getting dressed and undressed. She reported having preserved function in her right upper extremity and paralysis in her left upper extremity. The patient’s postacute rehabilitation goal is to improve her musculoskeletal function in order to return home and to be more independent in her everyday tasks.

Discussion. MMD is an extremely rare illness associated with abnormalities of the anterior and middle cerebral arteries and stenosis or occlusions in both internal carotid arteries.1 In fact, moyamoya is a Japanese word signifying “something hazy like a puff of smoke drifting in the air.” This is an illustrative description of the smoky angiographic appearance of the abnormal collateral vessels that are formed in order to compensate for the stenotic internal carotid arteries.

MMD is predominantly seen in Japanese individuals and is extremely rare outside of Asia and Eastern societies.2 MMD has an unknown etiology, but many studies have found that 10% to 15% of MMD cases are familial,3 and several epidemiologic studies consider a viral or bacterial infection to be the culprit in the development of the disease.4

The prevalence of MMD is reported to be 10 times higher in East Asia than in Western countries.5 In 2003, the incidence of MMD in Japan was 0.54 per 100,000 population.3 The incidence of MMD in the African American population is reported to be much lower, at 0.13 per 100,000.6 In addition, the authors of one study found that from 1987 to 1998, only 14 cases of MMD were reported African Americans in Washington and California; extrapolating these findings using 2000 Census data revealed that only 44 MMD cases would occur in African Americans annually.7

Data from a Japanese nationwide registry depicts a bimodal distribution of age of onset of MMD.8 This nationwide data comprising 2545 cases of MMD shows that the typical age at onset is approximately 10 years or at approximately 40 years. Furthermore, a cohort study by Duan and colleagues on 802 patients in China with MMD showed that the age onset is approximately from 5 to 9 years or from 35 to 39 years.9 Our patient first became symptomatic when she experienced her first stroke at age 48 and was diagnosed with MMD at age 53.

Finally, the presentation of the cerebrovascular accidents in our patient differs from the norm. Studies such as that by Kitamura and colleagues10 conclude that ischemic strokes prevail over hemorrhagic strokes in children, whereas hemorrhagic strokes are more common in adults. Ikezaki and colleagues in 1997 reported that hemorrhagic events were present in 51% of Japanese adults with MMD and 69% in Korean adult patients with MMD.11 Furthermore, the study showed that female patients with MMD accounted for 64% and 71% of hemorrhaging strokes in South Korea and Japan, respectively. Thus, it is surprising to see that our female patient had had 4 cerebrovascular accidents, all of which were ischemic in nature.


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